P256F — A/C Request B Circuit Range/Performance

What Does P256F Mean?

P256F is a diagnostic trouble code indicating: A/C Request B Circuit Range/Performance. This code relates to the powertrain system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P256F

⚠️ Check Engine Light (MIL) illuminated
⚠️ A/C Request B not operating within expected parameters
⚠️ Reduced efficiency or performance of related system
⚠️ Reduced engine performance

Common Causes

🔍 A/C Request B degraded or contaminated
🔍 Mechanical wear or binding in A/C Request B
🔍 Incorrect A/C Request B installed (wrong part number)
🔍 Related system mechanical issue affecting A/C Request B readings

Frequently Asked Questions

What does P256F mean?

P256F indicates: A/C Request B Circuit Range/Performance. The vehicle's computer has detected that the A/C Request B is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P256F?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P256F for extended periods may cause additional problems.

How much does it cost to fix P256F?

Repair costs for P256F typically range from $50 to $250, depending on the root cause. Simple wiring or connector repairs are on the lower end, while component replacement costs more. A proper diagnosis ($80–$150 at most shops) will identify the exact cause before committing to expensive parts.

What To Do Next

Possible Fixes

🔧 Inspect and clean A/C Request B
🔧 Replace degraded A/C Request B
🔧 Check for related mechanical issues affecting readings

1
Find your vehicle above
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2
Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

P256F: A/C Request B Circuit Range/Performance